Field of the Invention
The present invention relates to an IC testing apparatus for testing a semiconductor integrated circuit device (hereinafter referred to as an "IC"), more particularly relates to a tray transfer arm, a tray transfer apparatus using the arm, an IC testing apparatus, and a tray handling method.
This type of IC testing apparatus, called a "handler", conveys a large number of ICs held on a tray to the inside of a testing apparatus where the ICs are made to electrically contact a test head, then the IC testing apparatus is made to perform the test. When the test is ended, the ICs are conveyed from the test head and reloaded on trays in accordance with the results of the tests so as to sort them into categories of good ICs and defective ones.
In a conventional IC testing apparatus, the trays for holding the ICs to be tested or the tested ICs (hereinafter referred to the "customer trays") and the trays conveyed through the IC testing apparatus (hereinafter referred to as the "test trays") are different in type, so the ICs are reloaded before the test and after the test.
When reloading the ICs finished being test from the test tray to the customer tray, a number of empty customer trays corresponding to the different categories, such as "good ICs" and "defective ICs", are prepared and the ICs reloaded there from the test tray. When a customer tray becomes full, it is necessary to convey it out and prepare a new empty tray. Therefore, a device called a "tray transfer arm" is built into the IC testing apparatus.
In such a conventional IC testing apparatus, however, a large number of operation steps were required to convey the full customer tray out and set the next empty tray. In particular, since the setting of the next tray was the last step, there was the problem that the operation of reloading the ICs ended up being stopped during that interval and the throughput (number of ICs processed by the handler per unit time) falls.